Intercommunicating telephones.



PATENTE JULY 21, 1908.

, H. c. THOMSON.

INTERGUMMUNIGATING TBLEPHoNE.

APPLICATION FILED MAB. 20. 1907.

2 SEEN-SHEET 1 No. 893,820.. PATBNTBD JULY.21, 1908.

H. G. THUMSGN.

INTBRCGMMUNIGATING TELEPHONES.

APPLICATION FILED HARZO. 1907.

2 snmiTs-SHBET z.

UNITED ATENT oncles-fl HENRY e. 'eHeMsomoi eosieN; MASSACHUSETTS, AssIGNoR To ELECTRIC GooDsMiiNrl Facirneinoi-conmnv; F BosToN', MassacsUsiTTs, A coaeoaATioN oF MAINE.

INTEnooamUNIcATI-Ne TELEPHONES.

Patenzeda'uiy e1, 1908.

appresi-on cles March zo, i907.' Serin No. 363,333..

T o all whom it may concem.'

.1 Be it known that l, HENRY C. THOMSON, acitizen of the United States, residing at 1Bo ston' inf` Vthe county of Suffolk and YState of Massachusetts, (whose post-oice address is 115 Purchase street, Boston,.

Massachusetts,) have invented new and useful Improvements in Interco1n1nnnicat ing Tele-phones, of. which tbe/following iS e speoication.- i `.The invention relates to interconnnnmcatingtelephones and has for its primaryv object the elimination of the disadvantages Vand objections incident to theuse of a .jnnotion vllioicf such as is commonly ein;

.pleyed in this class of telephones*in inaking the -conjn e,ctio 1 skfyoinj the l instrinnentalities cengiedyjtlieielephone box or casing of each sgationwith the main conductor wires whichfccnnect the different sta-tions.. i

is Well known the jlinction box is tlsiiallydfnot always located'at or near the is located or in soine outl-ofthe-wfy place whjeftje Eit (is inet conveniently accessible.

Branch wires lead from the baclbcard ofv the telephone veasingcr box to the junction box where each branchfwire Ais-connected with the ioper main conductor wire of the ccblcwtipesby means of s 'junction box intffidnedffiito v th e in, thehiirst insta-nce,

at thej-jnnctiqnsbaox; unless great care is ex? ercised '1 Iu iaklng connections and:

cafgsg'is".` delays A and `Ainconve nience in cori rec'tiiig anyerrors or inf making tests. to locate f engi defectsufin the system. These obj'ecljiorxtllef;features are eliminated in' practicing the present invention leading the main cable wires which runlroin station vtostation 'directly-to the backboard of the .telephonecasing orboxl ofeaclrst'atio'n and there making connections directlyr `with.

1 the ,wires from`-the various instruinentalities "-With this construction and arrangcnw'nt,.A

in the box or casing.

thei'cuinbersome and expensive junction box.

is eliminated' and tHe-connections with the 'lnainbfcoiidnctor wires, atte-1 inade wh'ciej they` arc conveniently accessible bot-infor install' ing the apparatnsand for making any coifrections or tests. This construction also enables thebackboard to be put in place during the construction of a building and the main conductor` wisest@ fattached thereto, the box clipart of 'the casing carry ing the switcher other1 mechanisms; forthat station being secured to the backbcard after the interior finish of the room is conm pleted and the proper connections between these instrumentalities end the main conductor wires being readily and conveniently made. l

In order that the connecticns'between the station instrnxnentalities and the main line wiresmay 'be readily made, i provvide the baclboard of the telephone casinglwith a. series' of nxe'tai plates corresponding to `the number vof main conductor n iresinj the tine cables and provide each` niet@ with Atlnce binding'screwsy.one for attaching the end of 'the incoining niaiijnconductorwire, one vfor attaching; the end' ot the corresponds, ing outgoing inein conductor wire, and the third forconnecting the wire leading to the weer Pm '0f the c' netsw-s earned b T .the telephone casing or, ocof whichV thed wack."

boardformes part, f.

Any form of switching and calling niechanisn'i may be employed in practicing thefinvention and one suitable form of such mchanism is shown in the drawings which i have prepared to illustrate c concrete embodiment of the invention.

In these drawings'Fxgure bshows two sta` ystem provided with the present invention. ig. 2 is a view showing the backbocrd ot one of the telephone boxes or casings and also showing the mechanism carried by saidcss# ing- Figi 3 1s an enlarged elevatlon shjcwung-J one of the plates on the hackboaifd'; and Figc" 4 is a sectional view showing the sance.-

As shown 1n the drawings the cables 1 which contain the 1n ain conductor wires-con-loo nectmg the various stations of thes iy'stem;i

lead directiy to and from the backboards of the telephone: boxes or casings 2.fo1 the differentstations. The backboard 3 oteach telephone box is provided with a series ofinetl plates 4 correspondingiii-number to thcnnmber of main conductor wircsjn thccablesl... The englfof tions of an interconnnnnicetmg telephone nected b y means of a screw 5 with one of the -1 y lead 'fiom station to station-are connected hare connected to the plate indicated at T. B.,

rect any errors,

plates 4 and the end of the corresponding wire in the outgoing cable l is connected to` the same plate by means of a binding screw 6. For instance the main conductor wires of the ringing battery circuit are connected to the plate 4 indicated at R, B., the main conductor wires of the talking battery circuit the main conductor wires for the home station (the station indicated in Fig. 2) arevconnected to the plate H., the main conductor wires for the common return circuit are connected to the plate C. R., and the main conductor Wires for the different stations in the system are connected to the plates marked #l to #8, the telephone' mechanism being intended for use in a system having nine inter-communicating stations. p

Each plate 4 is provided with a third binding screw 7 by which a clip '8 is secured to the plate`4. Each clip 8 is connected with. a wire 9 leading to the proper part of the switch or otherniechanism carried rin the box 4 which is hingedjto the back 'plate' By means of theplates and binding screws on the backboard '3 the wires 9 leading from the various'instrumcntalities carried by the box @are directly connected with the main conductorl wires contained within the incoming and outgoing cables 1. With this construction the main conductor wires which directly to the backboard of each station so that the connection between the Wires 9 and these main conductor wires may be readily and accurately made and any changcsin the connections may be readily effected to cor- The main conductor wires struction of a building and thc connection i between the wires Q and these main conductor wires be made after the interior finish of the room in which thc telephone box. is located has been completed.

Without attemptingl to point out the various forms ol' mecl'ianism which may be employed in practicinr the invention, what I desire to claim is ze.

An intercoimnunicating teleplwne apparatus comprising a series of telephone boxes or casings, each containing switching and calling niechar'iism, a main conductor cable leading,r directly from box to box and containingstation'wiresl equal in number to the number oi stations, common retu'rn talking and ringing battery wires, metallic plates on the back-board of each box.- corresponding in number' to the number of main conductor wires in the main cable, means for connecting; the incomingI and outgoing inain cable wires to the respective plates and wires con- 'meeting the respective plates with the switching and calling mechanism, substantiallyas descriluid.4

In witness whereof, I have hereunto signed my name this iifteenth day of March, 1907,

in presence of two Witnesses.

'HENRY C. THOMSON. Witnesses: f' CHARLES W. WiLKiNs,l EDWIN d. FLYNN.

(sol 

